JPS6180685A - Reproducing device of digital disk record - Google Patents

Abstract

PURPOSE:To execute a scroll action at a high speed by providing a scroll instruction discrimination means for discriminating a scroll instruction from recognized picture data, a reference position modifying means and a read position reset means. CONSTITUTION:In terms of the initialization of a program, a microcomputer in a control circuit 101 sets the value of a display reference position Vret written in a RAM119 to phi1, and supplies an initializing signal in accordance with the value to a video RAM control circuit 121. Then the microcomputer in the con trol circuit 101 reads out subcodes R-W reproduced from a disk 111 through a subcode R-W detection circuit 116, and recognizes what kind of instruction they are in data. Then the microcomputer judges whether the data is a kind of scroll instruction or not. When the reproduced data is a scroll instruction, the judgement is made whether the instruction is a scroll instruction in the right direction or that in the left direction, and the value of the display reference position Vret written in the RAM119 is read out.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a digital disc record playback device, such as a CD (optical compact disc) system, which records image data together with audio data, and particularly relates to an image display system thereof.

[Technical background of the invention]

Currently, some audio equipment employs a digital recording and reproducing method that makes full use of PCM technology in order to achieve high fidelity reproduction and excellent operability. To explain this, taking the CD system as an example, this is made up of a transparent resin disk with a diameter of 12 cm covered with a metal thin film that forms bits (irregularities with different reflectances) corresponding to digital PCM data. A disk is rotationally driven using a CLv (constant linear velocity) method, and is reproduced in a linear tracking manner from the inner circumference side to the outer circumference side using an optical pickup incorporating a semiconductor laser and an optical conversion element.

Here, the disc includes subcode data for improving operability and realizing advanced functions along with audio data to be reproduced. This subcode data is each subcode P and subcode Q per frame.
, subcode R to subcode W. Of these, the subcode Q is called address data, and in the program area of the disc (within a radius of 25 to 58 mm), the recorded confession song number (TNO), verse number (
INDEX), elapsed time (TI crime), etc., and the lead-in area (23 to 25 m radius) located on the inner circumference side.
m) range, the start address of each song number is indicated as TOC (Table of Contents) data. In other words, this subcode Q is recorded so that a search operation for selectively reproducing the desired data to be reproduced from the vast amount of recorded information recorded on the disc can be performed quickly and accurately. At the same time, it is also used as display data. Further, the subcode P is a simplified version of the above subcode Qt, which is data that simply indicates the turning point of the confession, and is used in a simple playback device that does not have an advanced search function.

On the other hand, the subcode R-Wfl, which consists of 6 bits per frame, is not used on existing discs that only record audio data for playback, and has recently been used as image display data. It is being considered.

That is, this subcode data is intended to display an image on, for example, a TV screen in synchronization with audio data, and its specific structure and usage are currently being considered as follows.

In other words, the above image data is roughly divided into display image data in units called packs or image manipulation instructions such as scrolling the screen, and each data is divided into one unit as shown in FIG.
It consists of 44 (=24×6) bits. Here, symbol 0 is mode/item data and specifies a display screen mode as described later. Moreover, symbol 1 is the above image display data.

This is instruction data indicating the type of image manipulation command, and symbols 4 to 19 are data for each command. Symbols 2, 3, and 20 to 23 are parity data generated by Reed-Don-Romon codes, and the reproducing apparatus uses this to perform error determination and error correction.

Here, the display screen mode designated by the symbol O is a TV (television graphics) mode.

LINE (line graphic) mode, ZER
There are three types: O(-1!' 0 ) mode. Therefore,
TV mode means that one screen is divided into two as shown in Figure 7 1:a).
This mode assumes a display device such as a CRT display consisting of 88 x 192 dots, and is compatible with LIN.
E mode means that one screen has 288 pixels as shown in Figure 7(b).
This mode is assumed for all simple display devices, such as liquid crystal displays, which are configured with 24 x 24 dot pixels. These screens are 6×12 fonts, which are called fonts, as shown in FIG. 7(C).

There are 4 TV modes.
One screen consists of 8 x 16 fonts, and 48 x 2 fonts in LINE mode. The above-mentioned display image data in units of 1 back is data corresponding to this 1 font, and the data area of symbols 8 to 19 shown in FIG. 6 (
Data for each pixel in the font is stored in 6x12 bits). Therefore, for example, when displaying in TV mode, 768 (=48X16) are required to configure one screen.
It is necessary to record the data of the pack to the disk. Also, one pack of data is recorded at a cycle of approximately 3m5ec, and it takes 2.3 seconds (768 seconds) to display one screen.
X 3 m5ec) of time is required. In addition, TV
In this mode, a pre-selected 16-color palette allows for subtle expressions such as intermediate colors and complex color changes, allowing for vivid images to be displayed. Similarly, in the VCU mode, images can be displayed in eight colors. Also, among the above display screen modes, ZERO mode is a NOP (No 0 mode) that does not affect the screen currently being displayed.
Therefore, this ZERO mode data is recorded in all subcodes R to WK of discs that do not record images, as with existing discs.

On the other hand, the pack data in the TV mode, Lll, and IE mode includes an image manipulation command other than the display image data, as described above, and the type of the command is indicated by the instruction data of symbol 1.

Here, the above image manipulation command includes a scroll command for the entire screen (command to move the entire screen horizontally or vertically), a scroll command for only a specific row or column, or a preset screen command to fill the entire screen with one color. By combining these, it becomes possible to construct a visually varied and effective screen.

[Problems with background technology]

However, a digital disc record playback device (i1'
In order to freely control the display screen using digital signal processing technology, it is necessary to have a high-capacity image display function not found in conventional models, and in particular, it is necessary to improve the control system. It is something that For example, an image manipulation command includes a scroll command, but if this is executed by transferring data in a viteorum, the number of transfers will be enormous, making it impossible to process the image data to be played back in real time. It becomes possible. That is, T
When a scroll command that moves the entire screen horizontally or vertically is played in V mode, if this command is executed using the devioram transfer method, 288 x 192 dots (each dot is 4 bits indicating a color, and when the totator blinks, the background is 8-bit data of 4-bit data indicating color), that is, 55
It is necessary to sequentially read 296 dots of data and write them at positions corresponding to the scroll amount. Here, 1 do, r-
Assuming the transfer time per transfer is t-10 μsec, it takes 55296 x 10 Jsec to execute one scroll operation.
c = 0.55 sec, which means that the reproduced instruction (approximately 3 m5 ec cycle) cannot be executed in actual time.

[Purpose of the invention]

The present invention has been made in consideration of the above-mentioned problems, and an object of the present invention is to provide a digital disc record playback device that can perform scrolling operations at high speed.

[Summary of the invention]

As shown in FIG. 1, the digital disc record playback device of the present invention includes a playback means for reading out each of the above-mentioned data from a disc on which image data has been digitized together with audio data, and data read out by the playback means. image data detection means for detecting image data from the image data detection means, image data recognition means for recognizing the image data detected by the image data detection means, and display screen of a display device according to the image data recognized by the image data recognition means. A storage means (for example, a video RAM) into which corresponding pixel data is written, a control means for controlling writing/reading of data to and from the storage means, and a display data supply means for supplying data read from the storage means to a display device. , a scroll command determining means for determining a scroll command from the recognized image data; a reference position changing means for causing the control means to change a reference position for reading data when the scroll command is determined; The present invention is characterized by comprising a read position reset means for resetting the data read position when the read position is outside the storage area of the storage means.

[Embodiments of the invention]

An embodiment of a CD-type digital disc record playback device to which the present invention is applied will be described with reference to the drawings.

First, FIG. 2 shows a schematic electrical circuit system of the digital disc record reproducing apparatus in this embodiment.

In the figure, a control circuit (101) includes a microcomputer, an interface circuit, etc.
By selectively operating the keys of the tuna group (102), according to the program stored in the ROM (103),
The disc playback system (104)' is controlled to a predetermined state, and the display unit (105) and CRT display (
106) displays various types of information as will be described later.

Therefore, the disc playback system (104) is controlled by the control circuit (101).
) causes the disc playback system control circuit (107)? The disk motor (108) and the pickup feed motor (
109) is driven and the laser diode of the pickup (110) is turned on, the data recorded on the disk (111) is reproduced by the pickup (110), and the reproduced signal is sent to the RF signal detection circuit (112). Send. This RF signal detection circuit (112) detects the detected RF
The signal is separated into a signal supplied to the double signal servo circuit (113) and an EFM signal supplied to the demodulation circuit (114). here,
Servo circuit (113) Sends signals for applying focus servo and tracking servo to the R pickup (110''l), and also sends out signals for applying focus servo and tracking servo to the pickup feed motor (109).
Combined with the control signal from 7), it sends out a signal that performs the IJ near tracking servo. 1. The demodulation circuit (413) performs waveform shaping and EFM demodulation on the EFM signal, separates the synchronization signal that becomes subcode data, and sends the synchronization signal to the subcode Q detection circuit (115) and the subcode R- In addition to supplying the signal to the W detection circuit (116), the signal from which the synchronization signal has been separated is supplied to the D/A conversion circuit (117).
) - and the D/A conversion circuit (117)
The reproduced signal converted back to an analog signal is sent to the speaker (11
It is used to drive the 81' to produce sound. Also, the subcodes Qi and I detected by the subcode detection circuit (115)
In the case of TOC data in the J-doin area, the control circuit (1
01')? This data is loaded into the RAM (119) via the control circuit (101) and is used to perform necessary control functions such as a search function.
) on the display section (105).
It is used to make necessary indications such as

On the other hand, the image data of the subcode R-W detected by the subcode R-W detection circuit (=tS) is transmitted to the control circuit (101
) and the video ram control circuit (121) to a predetermined address in the video ram (122). Note that this video ram (122) is set to 1 in consideration of the TV mode.
Those having a capacity of pine between 92 and 256 are used. Further, the TV double signal generation circuit 123) reads out the pixel data in the video ram (122) and further adds signals such as a vertical synchronization signal and a horizontal synchronization signal to generate a signal for TV screen display. (106)
supply to. Here, the control circuit (101') reads pixel data in the video ram (122) by supplying a predetermined control signal to the video ram control circuit (121), and freely displays the image on the CRT display (106). It is possible to control the

Next, the control function that is a feature of this embodiment will be explained based on the above configuration. In other words, what is done here is to perform a scrolling operation at high speed as stated in the purpose of the present invention. Its operation is controlled by a microcomputer in a control circuit (101). Therefore, flowcharts of the scroll operation execution program written in the ROM (103) to drive the microcomputer are shown in FIGS. 3 and 4, and will be explained below. Although a horizontal scrolling operation will be explained here as an example, it is easily confirmed that a vertical scrolling operation can also be handled in the same way.

First, referring to FIG. 3, the control circuit (101)
In the initialization operation of the program, the microcomputer in the bidet sets the display reference position VretO value written in the RAM (119) to ■, and then the microcomputer in the control circuit (101) sets the subcode R. -W detection circuit (116) Subcodes R to W reproduced from the disk (ill)
and recognize what instructions are in that data. (Step ■) Then, it is determined whether the data is a scroll command, which is a type of image manipulation command. However, scroll commands include commands to scroll the entire screen horizontally or vertically, commands to scroll a specific line horizontally, commands to scroll a specific column vertically, etc.
The type is specified by the instruction command in the data structure shown in FIG. 6, and the scroll direction, scroll amount, etc. are specified by the data of symbol 7 and below. If the data reproduced here is other than a scroll command, a process corresponding to the data is executed, but a description of that process will be omitted here.

(Step ■) Therefore, when the reproduced data is a scroll command, the data of symbol 7 and below of the data is determined, and it is determined whether the command is a rightward scroll command or a leftward scroll command. (Step ■) And RAM (119)
The value of the display reference position Vret written in is read out. Further, the flow limit t is determined based on the data of symbols 7 and below of the reproduced scroll m command (hereinafter, this will be referred to as tn dot scroll). Based on both of these values, in the case of rightward scrolling, Vret = Vr
et-11, if it is to the left, Vret = Vret
+0 is calculated and the value is written into the RAM (119) again. (Step, B■) Next, the above display reference position Vret
The video ram control circuit (1
21) Supply VC and return to step (■). (Step 6)
) According to the above procedure, the display reference position VretO value changes every time scrolling in the left and right directions is executed. Note that when executing an instruction other than the scroll instruction in step ■, the origin position indicated by that instruction is
Set the value to , and execute. For example, when Vret=2 (font), if a command is received to write font' at horizontal position [5, vertical position 9, then horizontal direction 5+2=7
．． Write the font at position 9 in the vertical direction.

Next, video ram reading in the video ram control circuit (121) and TV signal generation circuit (123), CRT
The screen display procedure will be explained with reference to the flowchart shown in FIG. In addition, here, the y-th row on the screen is horizontally V
We will discuss the case of displaying in the order of c1st column to nth column, but the actual display processing is as follows: 1st line → 2nd line → ... → yth line →
y−+− is continued from the row →...,
Processing for other columns is similar to that below.

Therefore, in screen display processing, basically the video ram control circuit (121) reads data from the video ram (122), and the data 1! r: TV signal generation circuit (123)
Through the CRT display (106) the display of pixels on its screen is done on a flat head. here,
When displaying the y-th row horizontally, first, the horizontal display position of the screen is set to χD=■, and the horizontal read position on the video ram is set to χH=Vret. However, Vret refers to the display reference position mentioned above, and the control circuit 402 supplies a signal corresponding to the display reference position to the video ram control circuit 420. (Step ■) Next, as shown in FIG. 5(a), the video ram (122)
Pixel data indicated by the coordinates (χn, y) above (temporarily A.

B, C, L).
' to view. This is displayed at the position where the data in the video ram (122) is scrolled in the horizontal direction, as shown in FIG. 5(b). (Step, P■) Then, when all the pixels in the y-th row have been displayed, the display moves to the next 7+1 row, and the same procedure is repeated. (Step, P■) Also, if pixel display has not finished, set the horizontal display position ZD and readout position χR to zB = ZD + 1, respectively.
, χR=χm+1. That is, the display position and the read position # are each shifted by one position to the right.

Note that this operation is executed using a shift register installed in the video ram control circuit (121).
By performing this procedure, the video ram (122)
and the screen on the CRT display (106) have a one-to-one correspondence. (Step ■) Here, the horizontal address of the video ram (122) has a limit as shown in 5th Ca), and the video ram readout [ whose value was changed in the above step ■].

It is determined whether the value of the position χR is less than or equal to the limit value. Therefore, the readout point (arrow) in FIG. 5(a) that exceeds the limit value
As shown in , reset the first shift of χR and continue the above procedure as χR-Z. (Step ■) Therefore, with the above flat head, for example, Vret is Vret=Vret +
Just change it to 2 to scroll two dots to the left,
When Vret = Vret -2, two-dot scrolling to the right can be executed.

That is, according to the non-embodiment, when the scroll command is reproduced from the disk, the display reference position Vret.

Scroll operations can be easily performed by simply adding or subtracting values.
This method allows instructions to be processed much faster than the above-mentioned method of transferring data within a deoram.

Although one embodiment has been described in detail so far, the means for realizing the present invention are not limited to those described above and illustrated, and various modifications and applications are possible, allowing application of a wide range of means. It is something.

〔Effect of the invention〕

As explained above, the digital disc record playback at of the present invention can perform scrolling operations easily and at high speed.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the overall configuration of the present invention, FIG. 2 is a block diagram showing an electric circuit system in an embodiment of the digital disc record playback device according to the present invention, and FIGS. 3 and 4 are FIG. 5 is an explanatory diagram for explaining the display form in the operation of the embodiment, and FIGS. 6 and 7 are subsections related to the technical background of the present invention. FIG. 2 is an explanatory diagram for explaining the conceptual configuration and display screen mode of code R-W. 101...Control circuit. 104...Disc playback system. 116...Subcode R-W detection circuit. 121... Video ram control circuit. 122...Video Ram. 123...W signal generation circuit.

Claims (1)

[Scope of Claims] Reproduction means for reading out each of the above data from a disc in which digitalized image data to be displayed on a predetermined display device is recorded together with audio data, and reproduction means for reading the above data from the data read by the reproduction means. An image data detection means for detecting image data, an image data recognition means for recognizing the image data detected by the image data detection means, and a display screen of the display device according to the image data recognized by the image data recognition means. storage means into which corresponding pixel data is written; control means for controlling writing/reading of data to and from the storage means; display data supply means for supplying data read from the storage means to the display device; a scroll command determining means for determining a scroll command from image data that has been read; a reference position changing means for causing the control means to change a reference position for data reading when the scroll command is determined; and a data read position by the control means. 1. A digital disc record playback device comprising: readout position reset means for resetting a data readout position when the data is out of the storage area of the storage means.